This invention relates generally to the field of inserting machines, and more particularly to an apparatus for positioning envelopes having various shape and throat characteristics in an inserting machine so that insert material can be inserted into the different envelopes without causing the inserting machine to malfunction.
This invention is an improvement on the envelope inserting apparatus disclosed and claimed in U.S. Pat. No. 4,852,334, issued on Aug. 1, 1989 to David R. Auerbach, and assigned to the assignee of this application.
Envelope inserting machines have long been well known and have achieved a significant degree of commercial success, since they significantly increase the speed at which various forms of sheet material can be inserted into envelopes prior to the envelopes being inserted into a mailing machine where the flaps are closed and sealed and a postage indicia is applied to the envelopes.
Although there are a wide variety of envelope inserting machines both commercially available and in the prior art, a significant problem associated with all such machines is that of ensuring that the throat of the envelope is open sufficiently wide to receive the insert material. In actual practice, the type and quantity of sheet material typically inserted into envelopes by inserting machines of the type with which the present invention is concerned ranges from a single sheet, either shaped to fit within the envelope or folded to fit, to a plurality of such sheets, with perhaps single or folded inserts contained within the folded sheets, and running perhaps one eighth to one quarter of an inch thick. With this type of bulk material being inserted into the envelope, it becomes critical that the throat of the envelope be opened sufficiently wide so that the material will enter the envelope without snagging or catching on any portion of the edge of the envelope throat. Should this happen, the envelope becomes rumpled, the insert material becomes disarrayed and a serious paper jam occurs in the machine which usually requires that the machine be shut down, that various access doors or panels be opened, or portions of the machine be separated from other portions to render the area of the jam accessible to an operator for clearing, during all of which the inserting machine is inoperable. It will be apparent that this can have serious consequences if the inserting machine is on line with other machines, such as a collator and folder combination that forms the insert package for the inserting machine, and a continuous through put mailing machine for receiving the filled envelope from the inserting machine for closing and sealing the envelope and applying a postage indicia thereto.
Various attempts have been made in prior machines to address the problem of properly opening envelope throats so as to consistently receive insert material without causing misfeeds or jams, and most if not all of these attempts have met with varying degrees of success. Thus, virtually all of the inserting machines in commercial use today do effectively open envelope throats properly, that is, the envelope throats are opened by the throat opening mechanism on the first try and to an extent sufficient to accept the amount of material that is being inserted. In normal practice, the envelope is fed to a stop member which places the envelope in a predetermined position in which one of various forms of envelope throat opening devices spreads the non-flapped side of the envelope away from the flapped side to open the throat, after which the insert package is pushed into the envelope by a suitable pusher assembly. The throat opening devices then release the envelope, the stop is moved out of the path of movement of the envelope, and the filled envelope is ejected from the inserting machine for further processing.
In order for this process to occur, it is necessary to adjust the position of the stop member in the direction of feed of the envelope so that the upper edge of the non-flapped side of the envelope is in the precise predetermined position where the picker devices will catch on the upper edge of the non-flapped side of the envelope to open the throat. This typically involves placing an envelope into the inserting machine and manually positioning it back and forth by small increments in the direction of feed of the envelope, while also manually moving the picker devices back and forth during the actual envelop edge catching portion of the cycle of operation of the picker devices, until the operator is satisfied that the picker devices will properly catch on the upper edge of each succeeding envelope during a run to open all of them properly. Once the back stop has been properly adjusted for a particular envelope and is locked in position, the inserting machine will normally operate without further adjustment or difficulty.
The problem that arises is that the extent of the reliability of the envelope throat opening devices to perform their intended function is affected by the wide variety of shapes and configurations of envelopes that are available for normal business and private use, and the inserting machine may require adjustment as described above for each different type of envelope being used. For example, considering the typical #10 envelope so frequently used for business, any variation in the width of the envelope measured from the bottom to the crease line between the flap and the upper surface of the envelope will obviously vary the position of the envelope at the inserting location if the stop member remains in the same position. Also, and perhaps of greater significance, there is substantial variation in the shape of the non-flapped side of envelopes, some of which extend from the bottom edge thereof to a line substantially coincident with the crease line between the flap and the flapped side of the envelope, while other non-flapped sides have upper edges that extend downwardly from a position of coincidence with the crease line in various forms of V configurations. For example, on some envelopes, the non-flapped upper edge extends almost straight across the envelope for a short distance and then angles downwardly rather gradually to the center of the envelope. On others, the same upper edge may extend downwardly into the V configuration rather steeply and directly from the outer edge corners. A further factor that affects the reliability of the envelope flap opening device is the differences in the shape and/or configuration of envelopes due only to manufacturing tolerances, which in some instances can cause variations of as much as plus or minus one sixteenth of an inch.
As long as the inserting machine is readjusted as described above each time a different type of envelope is utilized, no difficulty is likely to be encountered be encountered in the operation of the inserting machine. And, of course, if the inserting machine is being used in connection with runs of many thousands of envelopes of the same shape and throat configuration, such repeated adjustment would not present a significant problem. However, the problem that often arises is that an operator, or some other person not familiar with the inserting operation currently running, may insert an envelope into the current run that has a different shape or throat configuration than that of the envelopes currently running, and the inserting machine may not be adjusted to properly open the throat on that envelope, thereby resulting in a jam with the consequences described above. The same result would occur if an operator changed to a different type of envelope from that of a previous run and did not readjust the inserting machine for the new envelope before starting a new run.
In view of the foregoing, there is obviously a need for an inserting machine that can recognize variations in shape and throat characteristics of envelopes and that can automatically position envelopes in response to such recognition so that the picker devices will properly open the throat of the different envelopes to receive the insert package. It should be apparent that an inserting machine with this type of capability would rarely if ever malfunction due to a change in the shape and throat characteristics of different envelopes.